IBM alphaWorks Releases JDK for Linux, Source for JavaBeans
Jun 11, 1999, 21:00 (6 Talkback[s])
Desktop-as-a-Service Designed for Any Cloud ? Nutanix Frame
Frank Carlos writes:
"IBM begins opening source for JavaBeans. Based on
customer demand, a subset of IBM's award-winning JavaBeans are now
available with source code. Downloaders can become members of the
'alphaBeans with Source' community."
"The release of the alpha version 1.1.6 of the IBM Developer Kit
continues IBM's strong commitment to the Linux and Java platforms
and communities. The Developer Kit is IBM's port of Sun's JDK(TM)
1.1.6 to the Linux operating system running on Intel architecture
based computers. The Developer Kit includes similar IBM
Just-In-Time (JIT) compiling technology found in IBM's high
performing, industry-leading Developer Kits for the OS/2 and
Windows** operating systems."
[ Here is the FAQ for the Linux JDK. -lt ed ]
1. On what Linux systems can I run the IBM Developer
A. We have tested it on: Caldera Open Linux 2.2 ®, Pacific
Hi Tech TurboLinux 3.6 ®, RedHat Linux 6.0 ®, SuSE Linux
Our expectation is this code will run on other Linux®
products that include the code requirements below. We welcome your
comments on our alphaWorks discussion forum to help us determine
the other Linux distributions that run well with our alpha
This port requires:
- Linux kernel 2.2 (all Linux distributions above contain the 2.2
kernel) For information on upgrading your system with a 2.2.x level
Linux kernel please see: http://www.kernel.org
- glibc 2.1 (Which ships with RedHat 6.0 and Caldera 2.2) You may
also download glibc 2.1 from the ftp site at
- LessTif 0.88.1 - you can download at no charge from www.lesstif.org b.) you may also
replace LessTif with Motif 2.1 if you have a license for it
2. Why did you develop a Java 1.1.6 version Developer
A. Our goal was to get a high performance developer kit in your
hands as quickly as possible. Using our 1.1.6 AIX port as a base
provided us with an effective way to achieve that objective.
Similarly, IBM's 1.1.6 JIT for Intel is proven technology that
provided a solid starting point for porting to Linux.
2b. What kind of performance do you see with this
A. Our limited testing experience on the Linux platform
indicates the code performs well. Please share your performance
experience with this code on our discussion forum by clicking on
the 'discussion button' .
3. What are the system requirements?
Computer: Intel 486 or better (Pentium recommended)
Disk Space: 9MB (to download) 30MB (to uncompress),
Memory: 32MB RAM
Display: Suitable for X-Window usage
Dependencies: Linux kernel 2.2, glibc 2.1, Motif ®/Lesstif 2.1
4. Where can I go for additional information on this
A. You can access our discussion forum that has been established
to collect your suggestions and ideas by clicking on the
'discussion button' at this site.
5. What Java programs are supported?
A. We are not supporting any programs with the alpha version of
the code. This code is intended for your evaluation only. There is
no support offered other than the alphaWorks discussion forum.
6. When will you make this a generally available
A. This is a technology offering. We have no specific plans at
this time to make this a commercial product. We are very committed
to the Linux platform and will continue to explore ways we can
satisfy the needs of the Linux community.
7. How can I ask questions or get support for this alpha
A. As an alphaWorks technology, no support is offered for this
code. We have established the discussion forum as a means for you
to share ideas and helps among the user community.
8. How do I install the code?
A. Please refer to the README file and the download instructions
available on alphaWorks for installation instructions.
9. How do I know if the code installed
A. You can run the 'java -fullversion' command to check whether
or not your PATH is set correctly to access the IBM Developer Kit.
The fullversion command will return a string that reports that the
java you are running is level 1.1.6, built by IBM and will list a
build date of the form l116-1999MMDD which shows the month and date
of the build. If you do not see a string like this or the command
generates an error, then you are not using the IBM Developer Kit.
Please see the README for further troubleshooting instructions.
10. How do I uninstall the code?
A. To remove the code, you can perform two simple steps. If you
have added the code to your path in your shell startup script,
remove the bin directory of the Developer Kit from your PATH. After
completing this step, go to the parent of the directory where you
installed the Developer Kit and type 'rm -fR <javarootdir>'
where <javarootdir> is the subdirectory name of your
installation. For example, if you have installed the Developer Kit
in /usr/ibm116, go to /usr and type 'rm -fR ibm116'. This will
remove the code from your system.
11. Can I install and use this software alongside any
existing Java TM developer kits?
A. Yes, you can. Simply install the IBM Developer Kit in a
separate directory from any other developer kits and use the PATH
variable to specify which one you wish to run. Instructions for
doing this are addressed specifically in the README. Look there for
12. How can I improve performance?
A. When running benchmarks or other memory intensive programs
which may require large amounts of heap, use the -ms and -mx
command line options to specify a heap size. For example, if you
wish to set the Java heap size to 64MB, specify '-ms 64m -mx 64m'
on the command line. By doing this, performance may be increased
since the initial heap size is large enough such that heap
expansion does not have to be performed in small increments up to
the working set of the application.
13. I seem to run into problems trying to use more than
around 200 threads. How can I increase the number of threads
available to my Java application or applet?
A: Since the IBM Developer Kit for Linux uses native threads,
the underlying architecture of Linux represents each thread as a
process. The kernel specifies a maximum number of processes per
user which creates a hard limit that is usually set to 256 tasks
per user. Therefore, if you wish to run a Java application which
requires more than 256 threads, you need to recompile the kernel
with a higher maximum task limit. The header file which requires
modification is located in the source tree of the kernel in
include/linux/tasks.h. A constant is defined in this file called
NR_TASKS, which is normally 512, but can be set as high as 4092 on
Intel Linux systems. Also, another definition in the same file is
MAX_TASKS_PER_USER which is defined as NR_TASKS/2. This can be
changed if you want non-root users to be able to create more
processes (or threads in our case) than half of the entire system
maximum. After changing these definitions you must recompile the
kernel. For information on kernel-specific issues, you can check
the main Linux kernel web site at http://www.kernel.org.
14. Where can I find a list of known problems with the
A. Please look in the README file that is packaged with the
software to find a list of known problems with this alpha release.
We would be interested to learn of any problems you discover with
the alpha code in our discussion forum.
15. Will IBM make the source code available for the IBM
Developer Kit for Linux® , Java TM Technology Edition,
A. IBM does not have the rights to provide the source code for
this Developer Kit.
16. Where can I find more information about Java and
Java TM2 offerings from IBM?
A. Please access the IBM web site at: www.ibm.com/java
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